TWI865819B - Compressors and compressor systems - Google Patents

Abstract

A compressor in one embodiment includes: a cylinder; a piston that can reciprocate in the cylinder; an intake space that can communicate with an operating chamber formed by the cylinder and the piston; an ejection space that can communicate with the operating chamber formed by the cylinder and the piston; a partition wall portion that is arranged in a manner to surround the operating chamber and divide the intake space and the ejection space; and a cooling medium path formed in the partition wall portion.

Description

Compressors and compressor systems

This disclosure relates to a compressor and a compressor system.

In a reciprocating compressor, generally speaking, an intake gas passage and an exhaust gas passage are provided in the casing. Therefore, the high-temperature exhaust gas and the low-temperature intake gas exchange heat through the wall of the casing, causing the intake gas temperature to rise before it is sucked into the cylinder. As a result, the intake gas expands before it is sucked into the cylinder, and the volume becomes larger, and the mass flow rate of the exhaust gas decreases to an extent that cannot be ignored. Therefore, the volumetric efficiency of the compressor is reduced, and when the reciprocating compressor is installed in a refrigeration system, the refrigeration performance may be reduced.

Therefore, as a mechanism to suppress the overheating of the compressor, for example, a pipe for flowing cooling water is installed inside the crankcase or the top cover. Patent documents 1 and 2 disclose a structure that suppresses the overheating of the intake gas by spraying a refrigerant liquid into the ejection space in the top cover and cooling the compressed ejected gas with the evaporation latent heat of the refrigerant liquid.

[Prior Art Literature] [Patent Literature]

[Patent document 1] Japanese Patent Publication No. 2010-53765

[Patent Document 2] Japanese Patent Publication No. 2011-163192

According to the structures disclosed in patent documents 1 and 2, the overheating of the inhaled gas can be suppressed by cooling the discharged gas. However, due to the influence of cooling the discharged gas, there is a risk of generating a large amount of frost on the surface of the compressor (such as the surface of the top cover or the shell). This structure that generates a large amount of frost is not good.

This disclosure is made in view of the above-mentioned problems, and its purpose is to reduce the risk of frost adhesion on the compressor surface and to suppress the heat input from the ejection space to the suction space, thereby preventing the reduction of the volume efficiency of the compressor due to the heat input from the ejection space to the suction space.

To achieve the above-mentioned purpose, the compressor disclosed in the present invention is equipped with: a cylinder; a piston that can be reciprocated in the cylinder; an intake space that can be connected to the working chamber formed by the cylinder and the piston; an ejection space that can be connected to the working chamber; a partition wall that is arranged in a manner of surrounding the working chamber to divide the intake space and the ejection space; and a cooling medium path formed in the partition wall.

In addition, the compressor system disclosed in the present invention comprises: the above-mentioned compressor; a refrigerant circulation circuit, which is connected to the above-mentioned suction space and the above-mentioned ejection space of the above-mentioned compressor; a condenser, which condenses the ejection gas ejected from the above-mentioned ejection space; and a branch circuit, which branches from the above-mentioned refrigerant circulation circuit on the downstream side of the above-mentioned condenser and is connected to the above-mentioned cooling medium circuit.

According to the compressor disclosed herein, since the cooling medium is supplied to the cooling medium path formed in the partition wall portion that partitions the suction space and the discharge space, the risk of frost adhering to the compressor surface can be reduced, and the heat input from the discharge space to the suction space can be suppressed, thereby preventing the reduction in the volume efficiency of the compressor due to the heat input from the discharge space to the suction space. In addition, in addition to the above-mentioned effects, the compressor system disclosed herein can suppress the reduction in COP (Coefficient Of Performance) when applied to a refrigeration system or a heat pump system.

10(10A,10B,10C,10a,10b):Compressor

10a: Low-stage compressor

10b: High-end compressor

12: Cylinder

14: Piston

16: Partition wall

18: Cooling media road

20: Suction valve

22: Blowout valve

24: Crankshaft

26: Connecting rod

28: Valve box

30: Valve plate

31: 1st flow channel

31a: Opening

32: Compress the casing

33:Through hole

34: Second flow channel

36: Supply Road

38: Supply pipe

39: Throttling Department

40: Exhaust route

42: Refrigerant discharge path

42a: Refrigerant discharge path

42b: Refrigerant discharge path

44: Insulating gasket

46: Top cover

46a: Opening

48: Bolts

50: Spray nozzle

52: Supply pipe

54: Bolts

56:Through hole

58: Exhaust route

60: Refrigerant discharge path

60a: Refrigerant discharge path

60b: Refrigerant discharge path

62: Connecting roads

70(70A,70B,70C,70D):Compressor system

72: Refrigerant circulation

72a: Middle Road

74: Condenser

76: Branch Road

76a: Branch Road

76b: Branch Road

77: Liquid pump

78: Pressure regulating valve

79: Expansion valve

80: Evaporator

82: Inhalation chamber

84: Spray room

86: Oil separator

88: Receiver

Sc: Operation room

Si: Inhale space

Sv: Ejection space

w: load media

Figure 1 is a front sectional view of a reciprocating compressor in an embodiment.

Figure 2 is a front sectional view of a reciprocating compressor in an embodiment.

Figure 3 is a front sectional view of a reciprocating compressor in one embodiment.

FIG4 is a system diagram of a compressor system in an implementation form.

FIG5 is a system diagram of a compressor system in an implementation form.

FIG6 is a system diagram of a compressor system in an implementation form.

FIG7 is a system diagram of a compressor system in an implementation form.

Below, several embodiments of the present invention are described with reference to the attached drawings. However, the dimensions, materials, shapes, and relative configurations of the components described in the embodiments or shown in the drawings are merely illustrative examples and are not intended to limit the scope of the present invention to these.

For example, expressions such as "in a certain direction", "along a certain direction", "parallel", "orthogonal", "center", "concentric" or "coaxial" that indicate relative or absolute configurations not only strictly indicate such configurations, but also indicate the state of relative displacement at an angle or distance within a tolerance or degree of obtaining the same function.

For example, expressions such as "same", "equal", and "uniform" that indicate the state of equality of things not only strictly indicate the state of equality, but also indicate the state of tolerance or the difference in the degree of obtaining the same function.

For example, an expression indicating a shape such as a quadrilateral or a cylinder not only indicates a shape such as a quadrilateral or a cylinder in the strict geometric sense, but also indicates a shape including a concave-convex portion or a chamfered portion within the range of obtaining the same effect.

On the other hand, the expression of "equipped with", "having", "equipped with", "including" or "containing" a constituent element is not a mutually exclusive expression that excludes the existence of other constituent elements.

FIG. 1 to FIG. 3 are front cross-sectional views of a compressor 10 (10A, 10B, 10C) of several embodiments. In FIG. 1 to FIG. 3, the compressor 10 (10A to 10C) has a cylinder 12 and a piston 14 that can reciprocate in the cylinder 12, and the cylinder 12 and the piston 14 form an operating chamber Sc. In addition, there are a suction space Si and a discharge space Sv that can communicate with the operating chamber Sc. Furthermore, a partition wall portion 16 is provided in a manner to surround the operating chamber Sc, and the partition wall portion 16 divides the suction space Si and the discharge space Sv. In the partition wall portion 16, a suction valve 20 for switching the connection state between the suction space Si and the operating chamber Sc and an ejection valve 22 for switching the connection state between the ejection space Sv and the operating chamber Sc are provided, and a cooling medium path 18 for flowing cooling medium is formed.

In the above-mentioned embodiment, the intake gas sucked into the intake space Si is sucked into the working chamber Sc through the passage opened and closed by the intake valve 20, and is compressed by the piston 14. The intake gas compressed to high temperature and high pressure is ejected into the ejection space Sv through the passage opened and closed by the ejection valve 22. By flowing the cooling medium through the cooling medium passage 18 formed in the partition wall portion 16 that partitions the intake space Si and the ejection space Sv, heat input from the ejection space Sv to the intake space Si can be suppressed, so that the reduction in volume efficiency of the compressor 10 caused by heat input from the ejection space Sv to the intake space Si can be suppressed. On the other hand, since the partition wall portion 16 disposed in the compressor 10 is separated from the compressor surface, the temperature drop of the compressor surface is suppressed. Therefore, the formation of frost on the compressor surface can be suppressed.

The embodiment shown in Fig. 1 to Fig. 3 constitutes a so-called reciprocating compressor. A crankshaft 24 is provided at the bottom, and a piston 14 is connected to the crankshaft 24 via a connecting rod 26. The piston 14 reciprocates inside the cylinder 12 by the rotation of the crankshaft 24. The exemplary reciprocating compressor shown in Fig. 1 to Fig. 3 is a reciprocating compressor in which two cylinders 12 are arranged in parallel relative to the crankshaft 24, and each piston 14 is connected to the crankshaft 24 in a manner of reciprocating at a phase angle of 180°. The upper surface of the cylinder 12 is closed by a valve box 28, and a top cover 46 is provided above the partition wall portion 16 to form an ejection space Sv. An opening 46a for delivering the ejected gas is formed on the top cover 46.

The cooling medium supplied to the cooling medium circuit 18 may be, for example, cooling water, antifreeze liquid, etc. Furthermore, when the compressor 10 is installed in a refrigeration system or a heat pump system, the refrigerant liquid can be used as the operating fluid of such systems.

In one embodiment, as shown in FIG. 1 and FIG. 2 , the partition wall portion 16 includes a valve plate 30 for holding the suction valve 20 and the discharge valve 22, and a cooling medium path 18 is formed in the valve plate 30. The valve plate 30 is cooled by flowing the cooling medium in the cooling medium path 18, thereby suppressing the heat input from the discharge space Sv to the suction space Si. In this way, the reduction in the volume efficiency of the compressor 10 caused by the heat input from the discharge space Sv to the suction space Si can be suppressed. On the other hand, since the discharge space Sv and the like are interposed between the valve plate 30 and the compressor surface (for example, the surface of the top cover 46), the temperature reduction of the compressor surface (for example, the surface of the top cover 46) is suppressed. Therefore, the formation of frost on the compressor surface can be suppressed.

In one embodiment, as shown in FIG. 1 to FIG. 3 , the compressor 10 (10A to 10C) has a built-in suction space Si for accommodating a compressor housing 32 of a cylinder 12 and a piston 14. In the embodiment shown in FIG. 1 and FIG. 2 , a first flow path groove 31 having an opening 31a on the compressor housing 32 side is formed on the valve plate 30, and the cooling medium path 18 is formed by the first flow path groove 31.

According to this embodiment, since the cooling medium path 18 is formed by the first flow path groove 31, there is no need to form a deep hole in the valve plate 30, and the cooling medium path 18 can be formed by cutting the surface of the valve plate 30. Thus, the processing for forming the cooling medium path 18 on the valve plate 30 becomes easy. In addition, since the first flow path groove 31 has an opening 31a on the side of the compressor housing 32, the suction space Si can be cooled by the cooling medium flowing through the cooling medium path 18.

In one embodiment, the first flow path groove 31 is formed into a circular shape so as to surround the cylinder 12. In the exemplary embodiment shown in FIG. 1 , the outer peripheral portion of the valve plate 30 is exposed on the outer side of the top cover 46. The cooling medium path 18 has a through hole 33 opened at the end surface of the peripheral portion, and a spray nozzle 50 is installed to spray the cooling medium to the through hole 33. Furthermore, a supply pipe 52 is connected to supply the cooling medium to the spray nozzle 50. The valve plate 30 can be uniformly cooled by the cooling medium sprayed in a mist form from the spray nozzle 50. In addition, on the supply side of the cooling medium and the opposite side of the compressor body, a connecting passage 62 connected to the cooling medium path 18 and the ejection space Sv is formed on the partition of the valve plate 30, and the cooling medium is discharged to the ejection space Sv through the connecting passage 62.

In the exemplary embodiment shown in FIG. 2 , a supply passage 36 for supplying a cooling medium to the first flow path groove 31 is formed in the wall of the compressor housing 32, and a supply pipe 38 for supplying the cooling medium to the supply passage 36 is connected. In this way, by forming the supply passage 36 in the wall of the compressor housing 32, it is easy to form a supply passage for supplying the cooling medium to the first flow path groove 31. In addition, a throttling portion 39 is provided at the outlet of the cooling medium supplied from the supply pipe 38 to the supply passage 36 opened in the cooling medium passage 18. The cooling medium becomes a mist by passing through the throttling portion 39 and is sprayed toward the cooling medium passage 18. The throttling section 39 is, for example, a plug having a plurality of small-diameter through holes connected to the supply path 36 and the cooling medium path 18. In other embodiments, the outlet opening diameter of the supply path 36 can be set to a small diameter instead of providing the throttling section 39, thereby exerting the throttling function. On the other hand, a discharge path 58 is formed on the compressor casing 32 on the opposite side of the compressor body relative to the supply path 36 to discharge the cooling medium from the first flow path groove 31 after cooling, and a cooling medium discharge path 60 is connected to the opening outside the discharge path 58.

In the compressor 10 (10B) shown in FIG. 2, even when the top cover 46 needs to be removed during maintenance, there is no need to remove the supply pipe 38 from the compressor casing 32, so the maintenance work becomes easy.

In the exemplary embodiments shown in FIGS. 1 to 3 , the compressor housing 32 also serves as a crankcase, and the crankshaft 24 is accommodated inside the compressor housing 32.

In one embodiment, a heat-insulating gasket may be inserted between the valve plate 30 and the laminated portion of the compressor housing 32. However, in this case, if a gasket is provided in the area of the first flow path groove 31, the cooling effect of the intake gas flowing through the intake space Si is blocked, so a gasket is not provided in the opening 31a.

In one embodiment, as shown in FIG. 3 , a second flow path groove 34 is formed on the surface of the compressor housing 32 on the valve plate 30 side, and the cooling medium path 18 is formed by the second flow path groove 34. According to this embodiment, by flowing the cooling medium through the cooling medium path 18, the partition wall portion 16 including the valve plate 30 can be cooled, so that heat input from the ejection space Sv to the suction space Si can be suppressed. Thereby, the reduction in the volume efficiency of the compressor 10 caused by the heat input from the ejection space Sv to the suction space Si can be suppressed. On the other hand, even if the cooling medium flows through the cooling medium path 18, the temperature drop of the compressor surface (e.g., the surface of the top cover 46) is suppressed because the ejection space Sv is interposed between the valve plate 30 and the compressor surface. Therefore, the formation of frost on the compressor surface can be suppressed. Furthermore, since the cooling medium path 18 can be formed by cutting the surface of the compressor casing 32, the cooling medium path 18 can be easily formed.

In one embodiment, as shown in FIG. 3 , since the cooling medium is supplied to the second flow path groove 34, a supply path 36 is formed in the compressor housing 32, and a supply pipe 38 is connected to the opening outside the supply path 36. On the other hand, a discharge path 40 for discharging the cooling medium from the second flow path groove 34 after cooling is formed in the compressor housing 32 on the opposite side of the compressor body relative to the supply path 36, and a refrigerant discharge path 42 is connected to the opening outside the discharge path 40.

In one embodiment, as shown in FIG. 3 , an insulating gasket 44 is installed on the contact surface between the valve plate 30 and the compressor housing 32. The insulating gasket 44 includes, for example, a region where the second flow path groove 34 is formed, and is installed on the entire contact surface between the valve plate 30 and the compressor housing 32. By providing the insulating gasket 44, heat input from the ejection space Sv to the suction space Si existing inside the compressor housing 32 can be effectively suppressed.

In one embodiment, as shown in FIG. 1 and FIG. 3 , the outer peripheral portion of the valve plate 30 is interposed between the outer peripheral portion of the compressor housing 32 and the outer peripheral portion of the top cover 46. Thus, by fastening the three layers of the outer peripheral portion of the top cover 46, the valve plate 30, and the compressor housing 32 together with fasteners such as bolts, it is easy to install the valve plate 30 on the compressor body. In addition, in the embodiment shown in FIG. 1 , since the end surface of the outer peripheral portion of the valve plate 30 is exposed to the outside of the compressor 10, it is easy to set the spray nozzle 50 at the opening of the through hole 33 connected to the cooling medium path 18.

In the exemplary embodiments shown in FIG. 1 and FIG. 3 , the top cover 46, the valve plate 30 and the outer peripheral portion of the compressor housing 32 are fastened together with bolts 48. The compressor 10 (10B) shown in FIG. 2 combines the outer peripheral portion of the top cover 46 with the outer peripheral portion of the compressor housing 32 with bolts 54, and the outer peripheral portion of the valve plate 30 is arranged on the inner side of the top cover 46.

FIG. 4 and FIG. 5 are system diagrams showing several embodiments of the compressor system 70 (70A, 70B). The compressor 10 (10A~10C) of the above embodiment is provided in the refrigerant circulation circuit 72 of the compressor system 70 (70A, 70B). The compressor system 70 has a refrigerant circulation circuit 72 connected to the suction space Si and the discharge space Sv of the compressor 10. The refrigerant circulation circuit 72 has: a condenser 74 for condensing the refrigerant gas discharged from the discharge space Sv; and a branch circuit 76, which branches from the refrigerant circulation circuit 72 on the downstream side of the condenser 74 and is connected to the refrigerant circuit 18.

The compressor system 70 (70A, 70B) constitutes a refrigeration system. The refrigerant gas ejected from the ejection space Sv is cooled and liquefied by the condenser 74, and most of the liquefied refrigerant is decompressed by the expansion valve 79 installed in the refrigerant circulation circuit 72, and evaporated by the evaporator 80 to cool the load medium w. The refrigerant gas vaporized by the evaporator 80 is sucked into the suction chamber 82 forming the suction space Si of the compressor 10. The refrigerant gas sucked into the suction chamber 82 is pressurized by the compressor 10 and ejected to the refrigerant circulation circuit 72 through the ejection chamber 84 forming the ejection space Sv. A branch path 76 is provided on the downstream side of the condenser 74, which branches from the refrigerant circulation path 72. The branch path 76 is connected to the refrigerant path 18 formed in the partition wall portion 16 of the compressor 10. A portion of the refrigerant liquid flowing through the refrigerant circulation path 72 is supplied to the refrigerant path 18 through the branch path 76 to cool the partition wall portion 16.

In the exemplary embodiment shown in FIG. 4 and FIG. 5, an oil separator 86 for separating refrigeration oil from the refrigerant gas ejected from the compressor 10 and a liquid receiver 88 for temporarily storing the refrigerant liquid condensed by the condenser 74 are provided. In addition, the compressor 10 is constructed as a reciprocating compressor.

A liquid pump 77 is provided in the branch passage 76 of the compressor system 70 (70A) shown in FIG. 4. Since the branch passage 76 and the ejection space Sv become the same pressure when the compressor system 70 (70A) is used as the compressor 10 (10A) shown in FIG. 1, the liquid pump 77 is required to supply the refrigerant liquid from the branch passage 76 to the refrigerant passage 18. By pressurizing the refrigerant liquid flowing through the branch passage 76 by the liquid pump 77, the refrigerant liquid can be supplied to the refrigerant passage 18. A pressure regulating valve 78 is provided on the downstream side of the liquid pump 77 as needed, thereby adjusting the pressure of the refrigerant liquid flowing through the branch passage 76. Since the refrigerant liquid flowing from the branch path 76 into the refrigerant path 18 evaporates under low pressure and absorbs evaporation heat from the surroundings, the partition wall portion 16 can be cooled.

Thus, heat input from the ejection space Sv to the suction space Si can be suppressed, and the reduction in volume efficiency of the compressor 10 caused by the heat input can be suppressed. In addition, when the compressor 10 is applied to a refrigeration system or a heat pump system as shown in the compressor system 70 (70A, 70B), the reduction in COP of the system can be suppressed. In addition, since the ejection space Sv and the like are interposed between the partition wall 16 and the compressor surface (for example, the surface of the top cover 46), the partition wall 16 is separated from the compressor surface, so the temperature reduction of the compressor surface (for example, the surface of the top cover 46) is suppressed. Therefore, the formation of frost on the compressor surface can be suppressed.

Since the compressor system 70 (70A) shown in FIG. 4 is equipped with a liquid pump 77, when the compressor 10 (10B) shown in FIG. 2 or the compressor 10 (10C) shown in FIG. 3 is used as the compressor 10, the refrigerant discharge path 42 or 60 can be connected to any location of the refrigerant circulation path 72 by appropriately setting the pressure of the liquid pump 77. It is preferable to connect the refrigerant discharge path 42 or 60 through the refrigerant circulation path 72 on the upstream side of the condenser 74 (for example, the refrigerant circulation path 72 between the oil separator 86 and the condenser 74) without returning the refrigerant used for cooling the partition wall portion 16 to the refrigerant circulation path 72 on the downstream side of the expansion valve 79. Therefore, the supply of refrigerant to the refrigerant circuit 18 will not reduce the performance of the compressor 10. In addition, since the amount of refrigerant injected from the high-pressure liquid is small, the effect of the liquid pump on the power increase is relatively small.

The compressor system 70 (70B) shown in FIG. 5 is an implementation form when the compressor 10 (10B, 10C) shown in FIG. 2 or FIG. 3 is used as the compressor 10. In this implementation form, the liquid pump 77 is not provided in the branch road 76, and the refrigerant discharge road 42 or 60 is connected to the refrigerant circulation road 72 between the expansion valve 79 and the compressor 10 (10B, 10C). Since the refrigerant circulation road 72 in the area is lower in pressure than the branch road 76, even if the liquid pump 77 is not provided in the branch road 76, the refrigerant liquid supplied from the branch road 76 to the refrigerant road 18 can be discharged to the refrigerant circulation road 72 in the area through the refrigerant discharge road 42 or 60. In addition, by controlling the complete vaporization in the cooling medium circuit, liquid backflow can be prevented.

The compressor system 70 (70C, 70D) shown in FIG. 6 and FIG. 7 includes a low-stage compressor 10a and a high-stage compressor 10b which are arranged in series in a refrigerant circulation circuit 72. The refrigerant gas ejected from the ejection chamber 84 of the low-stage compressor 10a passes through the refrigerant circulation circuit 72 (intermediate circuit 72 (72a)) arranged between the low-stage compressor 10a and the high-stage compressor 10b, and is supplied to the suction chamber 82 of the high-stage compressor 10b. The refrigerant gas supplied to the suction chamber 82 of the high-stage compressor 10b is further compressed and ejected from the ejection chamber 84 to the refrigerant circulation circuit 72.

The compressor system 70 (70C, 70D) shown in FIG6 and FIG7 constitutes a refrigeration system, and the refrigerant decompressed by the expansion valve 79 is evaporated by the evaporator 80, and the evaporation latent heat is absorbed from the load medium w to cool. In the exemplary embodiment shown in FIG6 and FIG7, two oil separators 86 for separating the refrigeration oil from the refrigerant gas ejected from the compressor 10 (low-stage compressor 10a and high-stage compressor 10b) and a liquid receiver 88 for temporarily storing the refrigerant liquid condensed by the condenser 74 are provided. In addition, the low-stage compressor 10a and the high-stage compressor 10b are constructed as reciprocating compressors.

In the embodiment of cooling the partition wall portion 16 of the low-stage compressor 10a, a branch path 76a is provided which branches from the refrigerant circulation path 72 on the downstream side of the condenser 74 and the upstream side of the expansion valve 79 and is connected to the refrigerant path 18 of the low-stage compressor 10a. As the low-stage compressor 10a, the compressor 10 (10A to 10C) shown in Figures 1 to 3 can be used. When the compressor 10 (10B, 10C) is used, the refrigerant discharge path 42a or 60a is connected to the intermediate path 72 (72a). The intermediate path 72 (72a) is lower in pressure than the branch path 76a. Therefore, the refrigerant liquid branched from the refrigerant circulation circuit 72 to the branch circuit 76a is discharged to the intermediate circuit 72 (72a) through the refrigerant circuit 18 and the connecting circuit 62 in the case of the compressor 10 (10A), and is discharged to the intermediate circuit 72 (72a) through the refrigerant circuit 18 and the refrigerant discharge circuit 42a or 60a in the case of the compressor 10 (10B, 10C).

In the embodiment of cooling the partition wall portion 16 of the high-stage compressor 10b, in the embodiment shown in FIG6, a branch path 76b is provided which branches from the refrigerant circulation path 72 on the downstream side of the condenser 74 and the upstream side of the expansion valve 79 and communicates with the refrigerant circulation path 72 of the high-stage compressor 10b. As the high-stage compressor 10b, the compressor 10 (10A to 10C) shown in FIG1 to FIG3 can be used. In the branch path 76b, a liquid pump 77 and a pressure regulating valve 78 are provided as needed. When the compressor 10 (10B, 10C) is used, the refrigerant discharge path 42b or 60b where the refrigerant is discharged after cooling the partition wall 16 in the refrigerant path 18 is connected to any location of the refrigerant circulation path 72. Since the refrigerant liquid diverted from the refrigerant circulation path 72 to the branch path 76 is pressurized by the liquid pump 77, it can be supplied to the refrigerant path 18 of the high-stage compressor 10b. The refrigerant after cooling the partition wall 16 returns to the refrigerant circulation path 72 through the refrigerant discharge path 42b or 60b.

Preferably, the refrigerant discharge path 42b or 60b is connected to the refrigerant circulation path 72 on the upstream side of the condenser 74 (for example, the refrigerant circulation path 72 between the oil separator 86 and the condenser 74). In this way, the refrigerant used for cooling the partition wall portion 16 is not returned to the refrigerant circulation path 72 or the intermediate path 72 (72a) on the downstream side of the expansion valve 79. Therefore, the supply of refrigerant to the refrigerant path 18 will not reduce the performance of the compressor.

In the embodiment of cooling the partition wall portion 16 of the high-stage compressor 10b, in the embodiment shown in FIG. 7, it is not necessary to provide a liquid pump 77 and a pressure regulating valve 78 in the branch path 76b. Instead, the refrigerant discharge path 42b or 60b is connected to the intermediate path 72 (72a). Since the pressure of the intermediate path 72 (72a) is lower than the pressure of the branch path 76b, the refrigerant supplied from the branch path 76b to the refrigerant path 18 can be smoothly discharged to the intermediate path 72 (72a) through the refrigerant discharge path 42b or 60b.

In the embodiment shown in FIG. 6 and FIG. 7 , both the low-stage compressor 10a and the high-stage compressor 10b are provided with a mechanism for cooling the compressors. Alternatively, the cooling mechanism may be provided only in one of the low-stage compressor 10a or the high-stage compressor 10b.

Furthermore, in other embodiments, the compressor system 70 can be applied to a single two-stage compressor. When the compressor system 70 is applied to a refrigeration system, the cooling effect of the low-stage compressor has the greatest impact on the refrigeration performance. The single two-stage compressor houses the low-stage compressor and the high-stage compressor in one housing. Therefore, the low-stage compressor is not easily affected by the temperature rise of the high-stage compressor. By applying the compressor system 70 to a single two-stage compressor, the refrigeration performance can be maintained at a higher level.

The contents recorded in the above-mentioned implementation forms can be grasped in the following manner, for example.

1) A compressor (10) of one embodiment comprises: a cylinder (12); a piston (14) which can reciprocate in the cylinder; an intake space (Si) which can communicate with an operating chamber (Sc) formed by the cylinder and the piston; an ejection space (Sv) which can communicate with the operating chamber; a partition wall (16) which is arranged to surround the operating chamber and divide the intake space and the ejection space; and a cooling medium path (18) which is formed in the partition wall.

According to this structure, by forming a cooling medium path in the partition wall that divides the suction space and the discharge space, the cooling medium flows in the cooling medium path, which can suppress the heat input from the discharge space to the suction space, thereby suppressing the reduction in the volume efficiency of the compressor caused by the heat input from the discharge space to the suction space. On the other hand, since the partition wall portion provided in the compressor is separated from the compressor surface, the temperature drop of the compressor surface (for example, the surface of the top cover 46) is suppressed. Therefore, the formation of frost on the compressor surface can be suppressed.

2) Another embodiment of the compressor (10) is the compressor (10) described in 1), which is provided with: a suction valve (20) for switching the connection state between the suction space (Si) and the operating chamber (Sc); a discharge valve (22) for switching the connection state between the discharge space (Sv) and the operating chamber; and a valve plate (30) for maintaining the suction valve and the discharge valve; and the cooling medium path (18) is formed on the valve plate serving as the partition wall portion (16).

According to this structure, by forming a cooling medium path in the valve plate, the cooling medium path is cooled, and the heat input from the ejection space to the suction space can be suppressed, so the reduction in the volume efficiency of the compressor caused by the heat input from the ejection space to the suction space can be suppressed. On the other hand, since the valve plate installed in the compressor is separated from the compressor surface, the temperature drop of the compressor surface (for example, the surface of the top cover 46) is suppressed. Therefore, the formation of frost on the compressor surface can be suppressed.

3) Another embodiment of the compressor (10) is the compressor described in 2), which comprises: a compressor housing (32) having the suction space (Si) for accommodating the cylinder (12) and the piston (14); and the valve plate (30) forms a first flow path groove (31) on the surface of the compressor housing side, and at least a part of the cooling medium path (18) is formed by the first flow path groove.

According to this structure, since at least a part of the cooling medium path is formed by the first flow path groove, when the cooling medium path is formed in the valve plate, it is not necessary to form a deep hole in the valve plate. Therefore, the processing of forming the cooling medium path becomes easy. In addition, since the first flow path groove has an opening on the compressor casing side, the suction space can be cooled by cooling the cooling medium flowing through the medium path.

4) Another embodiment of the compressor (10) is the compressor described in 1), which is provided with: a suction valve (20) for switching the connection state between the suction space (Si) and the operating chamber (Sc); a discharge valve (22) for switching the connection state between the discharge space (Sv) and the operating chamber; a valve plate (30) for maintaining the suction valve and the discharge valve; and a compressor housing (32) for accommodating the cylinder and the piston; and the compressor housing has a second flow path groove (34) formed on the surface of the valve plate side, and at least a part of the cooling medium path (18) is formed by the second flow path groove.

According to this structure, since the cooling medium path can be formed by cutting the surface of the compressor casing, it is easy to form the cooling medium path.

5) Another embodiment of the compressor (10) is the compressor described in 4), which is provided with: a heat-insulating gasket (44) which is installed on the contact surface between the valve plate (30) and the compressor housing (32).

According to this structure, by having the above-mentioned heat insulating gasket, heat input from the ejection space to the suction space located on the side of the compressor casing can be further suppressed.

6) Another embodiment of the compressor (10) is a compressor according to any one of 3) to 5), which comprises: a top cover (46) which forms the ejection space (Sv) together with the valve plate (30); and the outer peripheral portion of the valve plate is installed between the outer peripheral portion of the compressor casing (32) and the outer peripheral portion of the top cover.

According to this structure, the valve plate can be easily installed by fastening the outer peripheral parts of the top cover, valve plate and compressor housing together with fasteners such as bolts. In addition, since the outer peripheral part of the valve plate is exposed to the outside, it is easy to connect the refrigerant supply pipe to the refrigerant path formed in the valve plate from the outside.

7) A compressor system (70) of one embodiment comprises: the compressor (10 (10A, 10B, 10C)); a refrigerant circulation circuit (72) connected to the suction space (Si) and the ejection space (Sv) of the compressor; a condenser (74) for condensing the ejection gas ejected from the ejection space; at least one branch circuit (76) branching from the refrigerant circulation circuit at the downstream side of the condenser and connected to the cooling medium circuit (18); and a liquid pump (77) disposed on the branch circuit.

According to this structure, since the refrigerant liquid flowing through the above-mentioned branch path is pressurized by a pump, the refrigerant liquid can be supplied to the cooling medium path. In this way, the partition wall portion provided in the compressor is cooled, so the reduction in the volume efficiency of the compressor caused by the heat input from the ejection space to the suction space can be suppressed. Therefore, when the compressor system is applied to a refrigeration system or a heat pump system, the reduction in COP (coefficient of performance) can be suppressed. In addition, since the partition wall portion provided in the compressor is separated from the compressor surface, the temperature drop of the compressor surface is suppressed. In this way, the formation of frost on the compressor surface can be suppressed.

8) Another embodiment of the compressor system (70) is the compressor system described in 7), which comprises: a refrigerant discharge path (42, 60) for returning the refrigerant discharged from the refrigerant path (18) of the compressor (10 (10A, 10B)) to the refrigerant circulation path (72); and the refrigerant discharge path is connected to the refrigerant circulation path between the compressor and the condenser (74).

According to this structure, the refrigerant liquid pressurized by the liquid pump and supplied to the cooling medium circuit can be returned to the refrigerant circulation circuit on the high-pressure side between the compressor and the condenser. In this way, the refrigerant used in the cooling partition wall can be used as the operating refrigerant of the compressor, so the refrigerant supplied to the cooling medium circuit for cooling will not reduce the performance of the compressor.

9) A compressor system of one embodiment comprises: the compressor (10 (10B, 10C)); a refrigerant circulation circuit (72) connected to the suction space (Si) and the discharge space (Sv) of the compressor; a condenser (74) for condensing the discharge gas discharged from the discharge space; an expansion valve (79) for condensing the discharge gas discharged from the condenser; The condensate of the ejected gas is decompressed; at least one branch line (76) is branched from the refrigerant circulation line between the condenser and the expansion valve and connected to the refrigerant line (18); and a refrigerant discharge line (42, 60) is used to return the refrigerant discharged from the refrigerant line of the compressor to the refrigerant circulation line between the expansion valve and the compressor.

According to this structure, since the refrigerant circulation circuit between the expansion valve and the compressor is lower in pressure than the branch circuit, even if a liquid pump is not installed in the branch circuit, the refrigerant supplied to the refrigerant circuit can be returned to the refrigerant circulation circuit in the low-pressure area through the refrigerant discharge circuit.

10) A compressor system (70) of one embodiment comprises: a refrigerant circulation circuit (72); a low-stage compressor (10a) and a high-stage compressor (10b), which are arranged in series in the refrigerant circulation circuit; and a condenser (74), which is used to condense the ejected gas ejected from the ejection space of the high-stage compressor; and the low-stage compressor is composed of the compressor (10 (10A~10C)), which comprises: A branch (76a) which branches off from the refrigerant circulation circuit at the downstream side of the condenser (74) and communicates with the refrigerant circuit of the low-stage compressor; and a refrigerant discharge circuit (42a, 60a) which returns the refrigerant discharged from the refrigerant circuit (18) of the low-stage compressor to the refrigerant circulation circuit (intermediate circuit 72 (72a)) between the low-stage compressor and the high-stage compressor.

According to this structure, since the intermediate path is lower in pressure than the branch path 76a, the refrigerant gas after cooling the partition wall in the cooling medium path of the low-stage compressor can be returned to the intermediate path through the refrigerant discharge part.

11) A compressor system (70) of one embodiment comprises: a refrigerant circulation circuit (72); a low-stage compressor (10a) and a high-stage compressor (10b), which are arranged in series in the cooling circulation circuit; and a condenser (74) for condensing the ejected gas ejected from the ejection space (Sv) of the high-stage compressor; and the high-stage compressor is connected to the compressor (10 (10A~10C) ) and comprises: a branch path (76b) which branches from the refrigerant circulation path at the downstream side of the condenser (74) and communicates with the refrigerant path (18) of the high-stage compressor; a liquid pump (77) which is arranged in the branch path; and a refrigerant discharge path (42b, 60b) which returns the refrigerant discharged from the refrigerant path of the high-stage compressor to the refrigerant circulation path.

According to this structure, since the refrigerant liquid supplied from the branch path to the refrigerant path of the high-stage compressor is pressurized by the liquid pump, it can be supplied to the refrigerant path of the high-stage compressor, and the refrigerant after cooling the partition wall in the refrigerant discharge path can be returned to the refrigerant circulation path through the refrigerant discharge path.

12) A compressor system (70) of one embodiment comprises: a refrigerant circulation circuit (72); a low-stage compressor (10a) and a high-stage compressor (10b), which are arranged in series in the refrigerant circulation circuit; and a condenser (74), which is used to condense the ejected gas ejected from the ejection space (Sv) of the high-stage compressor; and the high-stage compressor is composed of the compressor (10 (10B, 10C)), which has : A branch path (76b) which branches from the refrigerant circulation path at the downstream side of the condenser and communicates with the refrigerant path of the high-stage compressor; and a refrigerant discharge path (42b, 60b) which returns the refrigerant discharged from the refrigerant path (18) of the high-stage compressor to the refrigerant circulation path (intermediate path 72 (72a)) disposed between the low-stage compressor and the high-stage compressor.

According to this structure, since the refrigerant liquid flowing through the branch path is at a higher pressure than the intermediate path, the refrigerant liquid supplied from the branch path to the cooling medium path of the high-stage compressor can return to the intermediate path through the refrigerant discharge path after the cooling partition wall.

10(10A): Compressor

12: Cylinder

14: Piston

16: Partition wall

18: Cooling media road

20: Suction valve

22: Blowout valve

24: Crankshaft

26: Connecting rod

28: Valve box

30: Valve plate

31: 1st flow channel

31a: Opening

32: Compress the casing

46: Top cover

46a: Opening

48: Bolts

50: Spray nozzle

52: Supply pipe

62: Connecting roads

Sc: Operation room

Si: Inhale space

Sv: Ejection space

Claims (10)

A compressor comprises: a cylinder; a piston which can reciprocate in the cylinder; a compressor housing which accommodates the cylinder and the piston and has a suction space which can communicate with an operating chamber formed by the cylinder and the piston; a top cover which is arranged above the compressor housing and forms an ejection space which can communicate with the operating chamber; and a valve plate which is arranged below the top cover and above the compressor housing in a manner of surrounding the operating chamber and forms the ejection space together with the top cover and separates the ejection space. The above-mentioned suction space and the above-mentioned ejection space are divided; a cooling medium path is formed in the above-mentioned valve plate; a suction valve is maintained by the above-mentioned valve plate to switch the connection state between the above-mentioned suction space and the above-mentioned operating chamber; and an ejection valve is maintained by the above-mentioned valve plate to switch the connection state between the above-mentioned ejection space and the above-mentioned operating chamber; and a first flow path groove is formed on the lower surface of the side of the above-mentioned compression casing of the part of the above-mentioned valve plate covered by the above-mentioned top cover; at least a part of the above-mentioned cooling medium path is formed by the above-mentioned first flow path groove. A compressor comprises: a cylinder; a piston which can reciprocate in the cylinder; a compressor housing which accommodates the cylinder and the piston and has a suction space which can communicate with an operating chamber formed by the cylinder and the piston; a top cover which is arranged above the compressor housing and forms a discharge space which can communicate with the operating chamber; a valve plate which is arranged below the top cover and above the compressor housing in a manner of surrounding the operating chamber and forms the discharge space together with the top cover and partitions the suction space. and the ejection space; a cooling medium path formed on the valve plate; a suction valve held by the valve plate for switching the connection between the suction space and the actuating chamber; and an ejection valve held by the valve plate for switching the connection between the ejection space and the actuating chamber; and a second flow path groove is formed in the upper surface of the compression casing opposite to the lower surface of the valve plate, in the portion covered by the top cover via the valve plate; at least a portion of the cooling medium path is formed by the second flow path groove. The compressor of claim 2 is provided with: a heat-insulating gasket installed on the contact surface between the valve plate and the compressor casing. A compressor as claimed in any one of claims 1 to 3, wherein the outer peripheral portion of the valve plate is installed between the outer peripheral portion of the compressor casing and the outer peripheral portion of the top cover. A compressor system, comprising: a compressor as claimed in any one of claims 1 to 4; a refrigerant circulation circuit connected to the suction space and the ejection space of the compressor; a condenser for condensing the ejection gas ejected from the ejection space; at least one branch circuit branching from the refrigerant circulation circuit at the downstream side of the condenser and connected to the cooling medium circuit; and a liquid pump disposed on the branch circuit. The compressor system of claim 5 is provided with: a refrigerant discharge path, which returns the refrigerant discharged from the refrigerant path of the compressor to the refrigerant circulation path; and the refrigerant discharge path is connected to the refrigerant circulation path between the compressor and the condenser. A compressor system, comprising: a compressor as claimed in any one of claims 1 to 4; a refrigerant circulation circuit, which is connected to the suction space and the ejection space of the compressor; a condenser, which is used to condense the ejection gas ejected from the ejection space; an expansion valve, which decompresses the condensate of the ejection gas condensed by the condenser; at least one branch circuit, which branches from the refrigerant circulation circuit between the condenser and the expansion valve and is connected to the cooling medium circuit; and a refrigerant discharge circuit, which returns the cooling medium discharged from the cooling medium circuit of the compressor to the refrigerant circulation circuit between the expansion valve and the compressor. A compressor system, comprising: a refrigerant circulation circuit; a low-stage compressor and a high-stage compressor, which are arranged in series in the refrigerant circulation circuit; and a condenser, which is used to condense the ejected gas ejected from the ejection space of the high-stage compressor; and the low-stage compressor is composed of the compressor of any one of claims 1 to 4, and has : A branch line that branches from the refrigerant circulation line at the downstream side of the condenser and is connected to the refrigerant circulation line of the low-stage compressor; and a refrigerant discharge line that returns the refrigerant discharged from the refrigerant circulation line of the low-stage compressor to the refrigerant circulation line between the low-stage compressor and the high-stage compressor. A compressor system, which comprises: a refrigerant circulation circuit; a low-stage compressor and a high-stage compressor, which are arranged in series in the above-mentioned cooling circulation circuit; and a condenser, which is used to condense the ejected gas ejected from the above-mentioned ejection space of the above-mentioned high-stage compressor; and the above-mentioned high-stage compressor is composed of a compressor of any one of claim items 1 to 4, and comprises: a branch path, which branches from the above-mentioned refrigerant circulation circuit on the downstream side of the above-mentioned condenser and is connected to the above-mentioned refrigerant path of the above-mentioned high-stage compressor; a liquid pump, which is arranged in the above-mentioned branch path; and a refrigerant discharge path, which returns the refrigerant discharged from the above-mentioned refrigerant path of the above-mentioned high-stage compressor to the above-mentioned refrigerant circulation circuit. A compressor system, comprising: a refrigerant circulation circuit; a low-stage compressor and a high-stage compressor, which are arranged in series in the refrigerant circulation circuit; and a condenser, which is used to condense the ejected gas ejected from the ejection space of the high-stage compressor; and the high-stage compressor is composed of a compressor as described in any one of claims 1 to 4, and the compressor system It is further provided with: a branch line which branches from the refrigerant circulation line at the downstream side of the condenser and is connected to the refrigerant circulation line of the high-stage compressor; and a refrigerant discharge line which returns the refrigerant discharged from the refrigerant circulation line of the high-stage compressor to the refrigerant circulation line disposed between the low-stage compressor and the high-stage compressor.